1. Technical Field
The present disclosure relates to a protection circuit, in particular, to a voltage regulator, an under-voltage protection circuit thereof, and a voltage regulation system for a batteryless voltage regulation system of an air conditioning alternator.
2. Description of Related Art
Nowadays, a mobile vehicle (such as an automobile, a bus, and etc.) generally equipped with a voltage regulation system having an air conditioning alternator and a battery-powered alternator, wherein the battery-powered alternator is electrically connected to a battery. The battery-powered alternator is capable of charging the battery and powering other electrical equipment equipped on the mobile vehicle with the electrical power generated therefrom. The air conditioning alternator is mainly used for regulating the operation of the air conditioning system. Moreover, the air conditioning alternator itself does not connect to the battery and instead the air conditioning alternator is operatively driven by an engine. Specifically, the air conditioning alternator utilizes a capacitor box in replace of the battery. That is, the voltage regulation system of the air conditioning alternator is a batteryless voltage regulation system.
However, whenever the air conditioning alternator operates abnormally, for example, when air conditioning alternator operates in an under-voltage condition as a result of the power cord being worn out forming short circuit, the warning lamp of the battery would not be alerted and triggered on to warn the driver as the air conditioning alternator is not coupled to the battery. Consequently, the operation of the air conditioning system might be severely impacted or even causing the batteryless alternator to burst into flame due to overheating when the air conditioning alternator continuously running abnormally, thereby increases the chance of mobile vehicle accident.